JP5542816B2 - Machine tools for non-circular workpieces - Google Patents

Description

  The present invention relates to a machine tool for a non-circular workpiece, in particular a non-circular lathe or a non-circular machining lathe, which is capable of oscillating motion and a tool support, and a tool that is relatively opposite to the tool support. Having a compensation member which is movable in the direction and used for impact isolation, so that the movement of the tool or the tool support is formed by a drive acting between the tool support and the compensation member It is related to the format.

  A machine tool of this type is known, for example, from German Offenlegungsschrift DE 1910996A1 and is used in particular for high-speed machining of non-circular rotating bodies or generally for high-speed actuated tool feed units. It is done. In this case, the impact isolation is performed in order to prevent the impact caused by the high-speed tool movement from being transmitted to the casing or the mounting portion of the casing with substantially perfect strength. Transmission of impact to the casing or the like adversely affects processing accuracy.

  By M. Weck, J. Hennig, the final report “Entwicklung und Einsatz einer hochdynamischen Werkzeugzustelleinheit mit hydrostatischer Lagerung in Forschungsgemeinschaft Ultrapraezisionstechnik e, V, Achen, Oktober 2002 In order to avoid sticking friction when guiding the tool support, the so-called stick-slip effect, aerostatic or hydrostatic guides are used for accuracy and smooth movement. While satisfying the requirements, rolling bearings have not been used due to the high actuation force and short travel distance.

  However, hydrostatic guidance requires high construction costs due to piping, supply devices, leakage prevention measures, and the like. Such high construction costs make machine tools expensive, prone to failure during operation under harsh conditions, and require frequent maintenance.

  An object of the present invention is to form a machine tool for a non-circular workpiece with a simple structure.

  In order to solve the above-mentioned problems, according to the configuration of the present invention, in the machine tool of the type described at the beginning, the tool support is supported by the rolling elements, and the compensation member is machined through a plurality of guide elements. Suspended in the casing part of the machine, and the compensation member has a compensation stroke that depends on the vibrational movement of the tool support of the compensation member within the range of the elastic deformation of the guide element. Thus, it has a mass that is a multiple of the mass of the tool support. In such a configuration, the compensation stroke is absorbed by the elastic deformation of the guide element, so that no additional aerostatic or hydrostatic support for the compensation member is required. In the present invention, the stick-slip effect can be avoided only by the support of the compensation member, whereas the support of the tool support has a sticking friction that must be overcome by an appropriate output setting of the drive. It was made based on this knowledge. In other words, in order to surely avoid the adverse influence of the impact on the machining accuracy, the compensation member can respond quickly without delaying the impact. This can be achieved by providing the compensation member with a support portion that does not generate adhesion friction. In the present invention, instead of a general aerostatic or hydrostatic bearing, means for suspending the compensation member from the casing portion via a guide element is used. Elastic deformation is possible within the stroke amount. Due to the definition of the mass ratio between the compensation member and the movable component, ie the tool and the tool support, the stroke of the compensation member is shortened to such an extent that the range of elastic deformation of the guide element cannot be exceeded.

  According to an advantageous embodiment of the invention, the mass of the compensation member is at least 3 times, in particular at least 5 times or at least 10 times the mass of the tool support that supports the tool. In such a mass ratio, the stroke motion generated during the normal machining operation of the machine tool is sufficiently converted to the compensation stroke motion of the compensation member, or is reduced or attenuated, and the compensation stroke of the compensation member is reduced. Experiments have shown that it is within the range of elastic deformation of the guide element. Therefore, the guide element guides the movement of the compensation member on one side and generates a return force in the opposite direction to the direction of the compensation stroke on the other side. An additional support for guiding or additional means for forming a return force can be omitted.

  In order to achieve a very linear guidance of the compensation movement of the compensation member, according to an advantageous embodiment of the invention, the guide element is stationary in the dimension in the direction of the compensation stroke of the guide element (eg thickness). Is significantly smaller than the dimension of the guide element in the lateral or vertical direction (eg width) relative to the direction of the compensation stroke, in particular compared to the dimension in the lateral or vertical direction (width) relative to the direction of the compensation stroke. And a shape smaller than one tenth. This defines an effective displacement direction of the guide element that matches the direction of the compensation stroke. With such a configuration, the compensation member is prevented from moving in the lateral direction or the vertical direction with respect to the direction of the compensation stroke, and as a result, high accuracy with little deviation of the movement from the straight line is achieved. Yes.

  In a particularly advantageous manner, the guide elements are each attached to one casing part on either side of the working plane predefined by the compensation stroke and each engages a compensation member between the attachment sites. The guide element may be formed in one piece or may be interrupted at the compensation member.

  According to a form of the invention, the guiding element prevents lateral movement of the compensation member or movement of the compensation member in a direction transverse or perpendicular to the direction of the compensation stroke. For this purpose, the guide element has a suitable geometry and / or is positioned or oriented and / or is appropriately engaged with the compensation member. Prevention of the movement of the compensation member in a direction transverse or perpendicular to the direction of the compensation stroke is to achieve a defined support of the tool support, and thus the tool, relative to the workpiece fixedly stationary relative to the casing part. It is necessary.

  According to a particularly simple form, the guide element is partly or entirely formed as a strip spring or leaf spring, which strip spring or leaf spring is generated by the compensation stroke of the compensation member. It acts in the opposite direction to the displacement.

  According to the embodiment of the present invention, each guide element is formed in a flat shape, a strip shape, or a band shape, and extends in a direction perpendicular to the direction of the compensation stroke or a lateral direction in a stationary position or a stationary state. Located in one plane, the orientation, shape and mounting of the guide element make the movement of the guide element along the plane, ie the movement of the guide element in the direction of the plane difficult. Thus, only the compensation member is guided in the compensation stroke direction. In other words, this embodiment shows a simple configuration for preventing the lateral movement of the compensation member or the lateral movement of the compensation member with respect to the direction of the compensation stroke.

  In order to achieve a very linear guidance of the compensation stroke of the compensation member or a guidance without deviation from the straight line, the guide elements are paired and are opposed in the direction of the compensation stroke of the compensation member. Engage with the end (8). With this arrangement, the guide elements have the greatest possible distance from one another, so that guidance at the correct angle of the compensation stroke can be achieved. In an advantageous form, the guide elements are clamped together in a rest position or in a rest state. By such tightening, the motion of the compensation member can be guided particularly well from the start of the motion.

  In order to obtain further improved stability to the side of the compensation member, a pair of guide elements extending parallel to each other and acting in parallel with each other at each end (interval) are engaged at each end of the compensation member. Match. In such a configuration, the mutual distance is preferably defined in a direction transverse or perpendicular to the direction of the compensation stroke.

  According to another aspect of the invention, each guide element is compensated with its end, which is attached to the casing part of the machine tool and is centrally located between said ends of each guide element. The member is engaged. As an additional configuration, or as a further alternative, the guide elements are engaged with the compensation member in pairs, one at each end, and another free end of each pair of guide elements. Is attached to the casing part of the machine tool in a direction away from it, in particular in the opposite direction.

  In order to perform the stroke of the tool supported by the tool support quickly and accurately, according to the embodiment of the present invention, the drive unit is formed by a linear motor, a plunger-type armature, a plunger-type armature or the like. . In an advantageous form, the drive is controlled by an adjustment circuit or a control circuit, the adjustment value or control amount being defined by the position of the tool support relative to the workpiece and / or the casing part. The

  In order to obtain an optimal mass ratio between the tool support and the compensation member and thus to achieve the desired conversion of the tool support stroke to the compensation stroke, it can be excited by energization of the stator or drive The component is coupled to the compensation member, and the magnetized component of the drive is coupled to the tool support. Components that can be excited by energization of the drive generally have a mass that is greater than the mass of the magnetized component or permanent magnet of the drive, and therefore the tool support and the compensation member including the tool. Is optimized by the configuration according to the above aspect of the present invention.

  In a particularly advantageous form, the tool support and its associated components have as little mass as possible so that the mass of the compensation member does not have to be chosen too large. For example, a slider is formed on the tool support, and the slider supports the permanent magnet of the linear motor. As a result, a compact structure with reduced mass can be obtained. Advantageously, the slider is formed of a lightweight structure.

  A further reduction in the weight of the component comprising the tool support is achieved by the permanent magnet supporting, ie reinforcing, the slider. That is, the permanent magnet has a dual function, and therefore, additional reinforcement of the slider for receiving the propulsive force generated by the electromagnetic force can be omitted.

  In order to obtain a particularly robust and light structure of the magnetized components of the drive, for example permanent magnets, according to an advantageous form, the magnetized components or permanent magnets are on both sides directed to the stator of the linear motor. Is covered by a cover or a carbon fiber plate, that is, in a particularly advantageous form, material-bonded or adhesively bonded to a cover or carbon fiber plate arranged between the stator of the linear motor. With the carbon fiber plate or carbon fiber reinforced plastic or carbon fiber composite, the stability of the overall structure, for example the stability of the drive, is improved with minimal increase in mass. The surface necessary to obtain a sufficiently high electromagnetic propulsion force by the arrangement of the cover also helps to stabilize the slider.

  In order to obtain a particularly simple and robust structure of the slider, potting material is injected in the intermediate space between the covers that receives the permanent magnets. By injecting potting material into the intermediate space, the shape stability of the slider is additionally obtained.

  In order to increase the coupling strength of the slider, the permanent magnet is advantageously fitted in a support structure formed on the slider.

  In order to achieve a simple and robust guide with sufficiently high accuracy for the movement of the tool support, rolling elements are engaged with the slider. According to an advantageous embodiment, the rolling elements are adapted to engage a rail fixed to the casing part, i.e. roll on the rail. With such a configuration, the rolling element forms a rolling bearing portion or a rolling bearing device that supports the tool support with respect to the casing portion, or supports the tool support with respect to the mechanical component fixed to the casing portion.

  According to the embodiment of the present invention, the stroke (stroke amount or stroke distance) of the vibration support of the tool support, and thus the tool, is smaller than the length of the circumference (outer circumference) of the rolling element of the rolling support portion. In such a configuration of the rolling element, the friction of the support portion of the tool support does not exceed the value required for the requirement of the accuracy of motion guide of the tool support.

  According to a particularly advantageous embodiment of the invention, the stroke of the vibration movement of the tool is between 0.01 mm and 45.00 mm and the compensation stroke (compensation stroke amount) is 2 mm or less or does not exceed 2 mm.

  Next, the present invention will be described in detail based on the illustrated embodiment, but the present invention is not limited to the illustrated embodiment. Each component recited in the claims can be used in various combinations.

It is a figure which shows the tool feeder of a machine tool seeing from the front side of a tool support body. It is sectional drawing along the AA line of the tool feeder of FIG. It is sectional drawing along the BB line of the tool feeder of FIG.

  A tool feed unit 1 of a machine tool for non-circular workpieces has a tool support 2, which is formed for receiving a tool and is adapted to oscillate. .

  A compensation member 3 is used for impact isolation, and the movement of the tool is generated or formed by a drive 4 acting between the tool support 2 and the compensation member 3. Although the acceleration generated by the drive unit 4 of the tool support 2 generates an impact, the impact is absorbed by the corresponding movement of the compensation member 3. Therefore, the impact caused by the acceleration of the tool support 2 does not act on other components of the machine tool, and as a result, the machining accuracy is not adversely affected.

  The tool support 2 composed of a plurality of components or connected to a plurality of components is supported by a plurality of rolling elements 5 and is only fixed to the tool support 2 with only one degree of freedom of movement. Guided so that only movement in the feed direction of the tool is allowed.

  The compensation member 3 is suspended via a plurality of guide elements 6 on the tool feed unit 1 and thus on the casing part 7 of the machine tool.

  The compensation member 3 is composed of a plurality of components, and has a mass that is a multiple of the mass of the tool support 2 that supports the tool.

  The guide element 6 is formed as a strip-shaped spring, which is located in one plane extending substantially perpendicular to the direction of the compensation stroke in the stationary state (non-actuated state). . The direction of the compensation stroke, i.e. the direction of the feed stroke, extends perpendicular to the drawing plane of FIG. Thereby, in FIG. 1, one working plane is defined which extends horizontally through the central axis of the tool support and perpendicularly to the drawing plane, and the central axis of the tool support is in the working plane. Each guide element is attached to the casing part on both sides of the working plane, i.e. above and below. Accordingly, the compensation member 3 is arranged and suspended between the upper mounting portion and the lower mounting portion of each guide element 6.

  As can be seen from the cross-sectional view of FIG. 2, the guide elements 6 are paired and engage the opposite ends 8 of the compensation member 3 in the direction of the compensation stroke extending in the drawing plane of FIG. Thereby, the compensation member 3 is suspended from the casing portion 7.

  As can be seen from FIG. 1, the guide elements 6 are paired and run parallel to each other at a distance from each other. In each pair of guide elements 6, each guide element 6 engages a laterally outer end of the compensation member 3 with respect to the compensation stroke.

  FIG. 3 shows that each guide element 6 is engaged with each corner of the compensation member 3 having a rectangular basic shape.

  As shown in FIG. 2, each guide element 6 is attached at its end 9 to the tool feed unit 1 and thus to the casing part 7 of the machine tool, and said end of each guide element 6. The compensation member 3 is engaged with a region 10 located in the center between the nine. In other words, the end 9 of the guide element 6 which is free, i.e. not directly engaged with the compensation member 3, is directed away from each other and in the opposite direction to the casing part of the machine tool 1 for suspension. 7 is attached.

  The linear motor 11 whose cross section is shown in the cross-sectional view of FIG. 2 forms a drive unit 4 for the movement of the tool support 2. The stator 12 of the linear motor 11 is a constituent part of the compensation member 3 and contributes to the mass of the compensation member 3. On the other hand, the magnetized (permanently magnetized) component 13 of the drive unit 4 is fixed (fixed) to the tool support 2. With such a configuration, the magnetized component 13 is displaced based on energization of the stator 12, and the tool support 2 is fed by the displacement.

  In order to receive the magnetized component 13 of the drive unit 4, a slider 14 is formed, which supports the permanent magnet 15 of the linear motor 11, on the permanent magnet and thus on the slider. A tool support 2 is attached.

  The slider 14 is formed of a lightweight structure, and a permanent magnet 15 reinforces the slider 14 and is covered with a cover 16 made of a carbon fiber composite material on both sides directed to the stator 12 of the linear motor 11. . An intermediate space 17 between the covers 16 for receiving the permanent magnets 15 is additionally injected with potting material or potting resin or sealing material, so that a material bond or adhesive bond between the permanent magnets 15 and the cover 16 is obtained. Has been used for.

  In order to increase the coupling strength of the slider 14, a lattice-like support structure or support pattern or support recess or support ridge not shown in the drawing is formed integrally with the slider 14.

  As shown in FIG. 1, the slider 14 is supported by engaging a plurality of rolling elements 5 with the slider. In other words, the rolling element 5 rolls on each rail block 18 on the one hand, and on the other hand guides the slider 14 in the direction of the work stroke (feeding stroke and return stroke) of the tool support 2. ing.

  The diameter of the rolling element 5 is selected so that the stroke of the vibration motion of the tool when the machine tool is operated is smaller than the circumferential length of the rolling element 5 of the rolling support portion. That is, the rolling element 5 does not rotate over the entire circumference during the work movement of the tool support 2 but substantially vibrates in one predetermined section. As is apparent from the cross-sectional view of FIG. 2, the rail block 18 is attached to a portion of the casing portion 7 that extends in a bridge shape within the receiving space of the compensation member 3, and the extending direction of the portion (extension) The direction) extends in parallel to the direction of the compensation stroke of the compensation member 3, and the portion passes through a hollow chamber formed in the compensation member 3.

  As is apparent from FIG. 2, the compensation member 3 is substantially composed of a frame 19 having a quadrangular cross section and a hollow inside, and a laminated stator 12 provided in the frame 19 of the linear motor. Has been. Accordingly, the mass of the compensation member 3 is substantially defined by the mass of the stator 12 and the mass of the frame 19.

  A tool feed unit 1 provided in a machine tool for a non-circular workpiece has a tool support 2 for receiving (supporting) a tool and a compensating member 3 for blocking an impact. This working movement is formed by a drive unit 4 that operates between the tool support 2 and the compensation member 3. According to this embodiment, the tool support 2 is supported by the casing part 7 of the tool feed unit 1 using the rolling elements 5, and the compensation member 3 is provided via the elastically deformable guide element 6. The mass of the compensation member 3 is suspended in a casing part 7 so that the compensation stroke of the compensation member 3 generated by the working movement of the tool support 2 is within the range of elastic deformation of the guide element 6. It is defined to be larger than the mass of the tool support 2 that supports the tool. The guide element 6 is adapted to guide and return the compensation member 3.

  DESCRIPTION OF SYMBOLS 1 Tool feed unit, 2 Tool support body, 3 Compensation member, 4 Driving part, 5 Rolling body, 6 Guide element, 7 Casing part, 8, 9 End part, 10 area | region, 11 Linear motor, 12 Stator, 13 Component part , 14 Slider, 15 Permanent magnet, 16 Cover, 17 Intermediate space, 18 Rail block, 19 Frame

Claims (13)

A machine tool for a non-circular workpiece, which is capable of vibration movement and a tool support (2), and is movable in the opposite direction relative to the tool support and for impact isolation It has a compensation member (3) used, so that the movement of the tool is generated or formed by a drive part (4) acting between the tool support (2) and the compensation member (3). The tool support (2) is supported by a rolling element (5), and the compensation member (3) is connected to the machine tool via a plurality of guide elements (6). The compensation member (3) is suspended from the casing part (7) of (1), and the compensation member (3) is a compensation stroke generated in response to the vibration motion of the tool support (2) of the compensation member (3). Is within the range of elastic deformation of the guide element (6). Have a multiple of the mass of the mass of the tool carrier for supporting (2),
The guide elements (6) are arranged in pairs in a direction perpendicular to the direction of the compensation stroke, and the end portions (3) of the compensation member (3) facing in the direction of the compensation stroke ( 8) is engaged,
Each said guide element (6) is attached to the said casing part (7) of the said machine tool (1) with the both ends (9), and both ends (9) of this each guide element (6) A machine tool for non-circular workpieces, characterized in that it is engaged with the compensation member (3) with a centrally located region (10).   The machine tool according to claim 1, wherein the mass of the compensation member (3) is at least three times the mass of the tool support (2) that supports the tool. When the guide element (6) is stationary, the dimension of the guide element (6) in the direction of the compensation stroke is greater than the dimension of the guide element (6) in the direction transverse to the direction of the compensation stroke. It is significantly smaller and has a shape smaller than one tenth of the dimension in the transverse direction with respect to the direction of the compensation stroke, and / or the guide element (6) of the compensation member (3), It is adapted to prevent movement in the transverse direction to the direction of the compensating stroke machine tool according to claim 1 or 2.   The guide element (6) is partly or entirely formed as a strip-shaped spring acting in the opposite direction to the displacement generated by the compensation stroke of the compensation member (3), and Each guide element (6) is formed in a flat or strip shape, and is substantially located in one plane extending in a direction perpendicular or transverse to the direction of the compensation stroke in a stationary state. The machine tool according to any one of claims 1 to 3.   The machine tool according to any one of claims 1 to 4, wherein the drive unit (4) is a linear motor (11), a plunger-type armature, or a plunger-type armature. The stator or the component that can be excited by energization of the drive unit (4) is coupled to the compensation member (3), and the component (13) that is permanently magnetized of the drive unit (4) is The tool support (2) is coupled to the tool support (2) and a slider (14) is formed. The slider supports the permanent magnet (15) of the linear motor (11). The machine tool according to claim 5 , wherein the permanent magnetized component (13) comprises the permanent magnet (15). The machine tool according to claim 6, wherein the permanent magnet (15) reinforces the slider (14). The permanent magnet (15) is covered with a cover (16), which is a carbon fiber plate, and / or material-bonded on both sides of the linear motor (11) facing the stator (12). The machine tool according to any one of 5 to 7. 9. The machine tool according to claim 8 , wherein an intermediate space (17) for receiving the permanent magnet (15) between the covers (16) is filled with potting material. The machine tool according to any one of claims 6 to 9, wherein the permanent magnet (15) is fitted in a support structure. Said tool carrier (2) and / or the slider (14), the is supported in the casing part (7), or claim 6 which is supported on a fixed component on the casing part (7) The machine tool according to any one of 10.   The machine tool according to any one of claims 1 to 11, wherein a stroke of the vibration motion of the tool is smaller than a circumferential length of the rolling element (5) of a rolling support portion.   The machine tool according to any one of claims 1 to 12, wherein a stroke of the vibration motion is 0.01 mm to 45.00 mm, and the compensation stroke is 2 mm or less.

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